Spinner oder Fortschrittsbalken an, während die Bilder geladen werden, werden nicht blockiert, UI

Können Sie aufblasen, benutzerdefinierte layout in getView() Methode in Ihrer ImageAdapter (check Beispiel auf der offiziellen Google-website http://developer.android.com/resources/tutorials/views/hello-gallery.html) z.B.:

public class ImageAdapter extends BaseAdapter {

    private ProgressBar mProgressBar;
    private ImageView mImageView;
    private String[] mUrls = {
        "http://apod.nasa.gov/apod/fap/image/0011/arcadenov9_trace.jpg",
        "http://apod.nasa.gov/apod/fap/image/0011/earthlights_dmsp_big.jpx",
        "http://apod.nasa.gov/apod/fap/image/0011/earthlights2_dmsp_big.jpx"
    }
    private boolean[] flags = new boolean[3]; //3 images example
    private LayoutInflater mInflater;

    public ImageAdapter(Context c) {
        mInflater = (LayoutInflater) c.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

    public int getCount() {
        return 3;
    }

    public Object getItem(int position) {
        return position;
    }

    public long getItemId(int position) {
        return position;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        convertView = mInflater.inflate(R.layout.gallery_item, null);
        if (!flags[position]) {
            image = convertView.findViewById(R.id.idImage);
            progressBar = convertView.findViewById(R.id.idProgressBar);
            new DownloadTask(image, progressBar, mUrls[position]).execute();
            flags[position]=true;
        }
        convertView.setLayoutParams(new Gallery.LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
        return convertView;
    }

Wo gallery_item.xml sieht wie folgt aus:

    <?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_gravity="center"
        android:gravity="center" >

        <ProgressBar
            android:id="@+id/idProgressBar"
            style="?android:attr/progressBarStyleSmall"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center" />

        <ImageView
            android:id="@+id/idImage"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center" />

    </LinearLayout>

In getView() - Methode übergeben werden können ProgressBar-und Bildansicht Instanzen zu DownloadTask (Klasse, die Sie erweitert AsyncTask) z.B.

new DownloadTask(image, progressBar, mUrls[position]).execute();

In doInBackground() sollten Sie herunterladen (und/oder irgendwie-cache/persistent) Bild (URL steht in mUrls[position]) und in onPostExecute() (run in UI thread) Sie sollten:

progressBar.setVisibility(View.GONE); //hide progress
imageView.setImageBitmap(bitmap); //set image

Als show-Fall Sie können eine Aktivität nur mit main.xml layout:

    <?xml version="1.0" encoding="utf-8"?>
    <Gallery xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/idGallery"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" />

InformationsquelleAutor Dragan Marjanović

versuchen, diesen code

private void showProgrssBar(){
pLayout.setVisibility(View.VISIBLE);
final StringBuffer s=new StringBuffer();
final Thread progressThread=new Thread(){
    @Override
    public void run(){


            while(CreateVideoService.processingFrame>1) {
                 inc=100-((CreateVideoService.processingFrame*100)/(CreateVideoService.numberofRecordedFrames));
                 if(s.length()>0)
                 s.delete(0, s.length());
                 s.append("Processing... ").append(inc).append("%");
                 progressBarHandler.post(new Runnable() {

                    @Override
                    public void run() {
                        //TODO Auto-generated method stub
                        progressBar.setProgress(inc);
                        textProgrs.setText(s); 
                    }
                });
                 //progressBar.setProgress(100-inc);
                 try {
                     //Sleep for 5 seconds
                     Thread.sleep(200);
                 } catch (InterruptedException e) {
                     //Log.d("TAG", "sleep failure");
                 }
            }
            layoutHandler.post(new Runnable() {

                @Override
                public void run() {
                    //TODO Auto-generated method stub
                    pLayout.setVisibility(View.GONE);
                }
            });

    }
};
progressThread.start();

}

InformationsquelleAutor ultimate